#ifndef FUNCGEN_UTIL_H_
#define FUNCGEN_UTIL_H_

#include <stdint.h>
#include <avr/eeprom.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>

/* Some of these macros are derived from the Linux Kernel sources. */

#define likely(x)		__builtin_expect(!!(x), 1)
#define unlikely(x)		__builtin_expect(!!(x), 0)

#undef offsetof
#define offsetof(type, member)	((size_t)&((type *)0)->member)

#define min(a, b)		((a) < (b) ? (a) : (b))
#define max(a, b)		((a) > (b) ? (a) : (b))

#define abs(x)			((x) >= 0 ? (x) : -(x))

#define ARRAY_SIZE(x)		(sizeof(x) / sizeof((x)[0]))

/* Memory barrier.
 * The CPU doesn't have runtime reordering, so we just
 * need a compiler memory clobber. */
#define mb()			__asm__ __volatile__("" : : : "memory")

/* Function annotation. Warn if the return value is unused. */
#define WARN_UNUSED_RES		__attribute__((__warn_unused_result__))

/* Convert something indirectly to a string */
#define __stringify(x)		#x
#define stringify(x)		__stringify(x)

/* Progmem pointer annotation. */
#define PROGPTR			/* progmem pointer */

/* Assertions */
void panic(const char PROGPTR *msg) __attribute__((noreturn));
#define BUILD_BUG_ON(x)		((void)sizeof(char[1 - 2 * !!(x)]))
#define BUG_ON(x)					\
	do {						\
		if (unlikely(x))			\
			panic(PSTR(__FILE__		\
			      stringify(__LINE__)));	\
	} while (0)

/* Delay */
void mdelay(uint16_t msecs);
void udelay(uint16_t usecs);

typedef _Bool		bool;


static inline void irq_disable(void)
{
	cli();
	mb();
}

static inline void irq_enable(void)
{
	mb();
	sei();
}

static inline uint8_t WARN_UNUSED_RES irq_disable_save(void)
{
	uint8_t sreg = SREG;
	cli();
	mb();
	return sreg;
}

static inline void irq_restore(uint8_t sreg_flags)
{
	mb();
	SREG = sreg_flags;
}


/* Jiffies timing helpers derived from the Linux Kernel sources.
 * These inlines deal with timer wrapping correctly.
 *
 * time_after(a, b) returns true if the time a is after time b.
 *
 * Do this with "<0" and ">=0" to only test the sign of the result. A
 * good compiler would generate better code (and a really good compiler
 * wouldn't care). Gcc is currently neither.
 */
#define time_after(a, b)	((int16_t)(b) - (int16_t)(a) < 0)
#define time_before(a, b)	time_after(b, a)


#undef __naked
#define __naked		__attribute__((__naked__))
#undef __used
#define __used		__attribute__((__used__))


#endif /* FUNCGEN_UTIL_H_ */